Refactoring the Collection component

Next, let’s refactor our Collection component. Replace the existing Collection component with the following:

import React, { Component } from ‘react’;
import ReactDOMServer from ‘react-dom/server’;
import CollectionControls from ‘./CollectionControls’;
import TweetList from ‘./TweetList’;
import Header from ‘./Header’;
import CollectionUtils from ‘../utils/CollectionUtils’;
import CollectionStore from ‘../stores/CollectionStore’;

class Collection extends Component {
  state = {
    collectionTweets: CollectionStore.getCollectionTweets()
  }

  componentDidMount() {
    CollectionStore.addChangeListener(this.onCollectionChange);
  }

  componentWillUnmount() {
    CollectionStore.removeChangeListener(this.onCollectionChange);
  }

  onCollectionChange = () => {
    this.setState({
      collectionTweets: CollectionStore.getCollectionTweets()
  ...